1. Field of the Invention
The present invention relates to a technique for assembling a magnetic head slider and a magnetic storage device. More specifically, it relates to a technique which is effective for an application to a magnetic disk device or the like having a contact type magnetic head slider.
2. Description of the Related Art
In an information processing field, a magnetic storage device including a rotational type storage medium is widely used as an external storage device or the like, and there is a great need to reduce its size and to increase its capacity.
For example, in a magnetic disk device including a magnetic disk as the rotational type storage medium, the smaller a space between the rotating magnetic disk and a magnetic head slider mounting a magnetic head for recording/reproducing information on this magnetic disk becomes, the higher the areal density capable of recording/reproducing the information on the magnetic disk which is a recording medium becomes. Thus, the space between the magnetic head slider and the magnetic disk becomes increasingly smaller. The present space between the magnetic head slider and the magnetic disk is less than 100 nm, and a the magnetic disk device having a space of 50 nm or less is also appearing on the market. Thus, a mainstream of the magnetic disk is a sputtering disk on which a magnetic material layer is formed by a sputtering process, thereby improving smoothness on a surface of the magnetic disk.
In order to further increase the areal density, the space between the magnetic head slider and the magnetic disk is further reduced, thereby also developing a contact recording form in which the magnetic head slider and the magnetic disk make contact intermittently with each other or are always in contact with each other.
Unlike a conventional flying type magnetic head slider, the contact recording requires a, resistance to wear due to a contact with the magnetic disk and a low friction force for keeping constant the space between the magnetic head and the magnetic disk. More specifically, assuming that a flying height of the conventional magnetic head slider is reduced and the head slider with reduced air bearing height is used for the contact recording, when the friction force is applied between the magnetic head slider and the magnetic disk, it is considered that a pitch angle of the magnetic head slider is reduced and thus the friction force is applied to a leading edge side of the magnetic head slider. The pitch angle is defined to be positive at the time of the high flying height on a leading edge of the magnetic head slider, while it is defined to be negative at the time of the high flying height on a trailing edge of the magnetic head slider. A reduction of the pitch angle allows the leading edge of the magnetic head slider to come into contact with the magnetic disk, whereby the friction force becomes still larger and thus a self-excited vibration of a suspension is generated. Furthermore, when a friction coefficient within the magnetic disk surface has a distribution, a forced vibration of the suspension is generated due to a variation in the friction force. Therefore, there is a technical problem in which the space between the magnetic head and the magnetic disk cannot be constantly kept and a stable magnetic recording is thus difficult.
As a method for solving this technical problem, an RCC (Remote Centered Compliance) mechanism is disclosed in Japanese Patent Unexamined Application No. 2-192082, for example. That is, this mechanism is constituted so that the front and rear portions of the magnetic head in a direction of rotation of the medium may be supported by a pair of front and rear inclined plates forming an inverted trapezoid with respect to the magnetic disk surface, an intersection of extending lines of the plates being at a height of the magnetic disk surface or lower. By the use of this mechanism, since the pitch angle is increased when the friction force is applied, an increase of the friction force can be prevented, and the self-excited vibration and forced vibration of the suspension can be suppressed. However, there is another technical problem in which, since this mechanism is complicated in structure, it is difficult to apply this method to the magnetic disk device.
In another publication, Y. Mitsuya, Y. Ohshima and T. Nonogaki, "Coupling and Nonlinear Effects of Cantilever Deflection and Torsion Encountered in Simultaneous Measurement of Vertical and Lateral Forces using a Scanning Probe Method", Proceedings of the 7th NORDTRIB '96, Vol. 3, for example. As regards a probe suspension of a probe microscope, a relationship between the force applied to a probe chip supported by the end of the cantilever in a direction perpendicular to the surface to be scanned and the force applied to the probe chip horizontally in a direction of the side surface of the cantilever is quantitatively analyzed by a method such as a finite element method. As a result, the publication merely proves an existence of an "optimum condition" in which, when the cantilever is deflected due to an application of the vertical force of a specific value to the cantilever, the cantilever is not distorted even if the lateral force is applied to the probe chip, the vertical and lateral forces are not correlated with each other, linearity is excellent and the simultaneous measurement of the vertical and lateral forces is allowed to be possible. The publication does not take into consideration the above technical problems to be solved by the present invention at all.
Thus, the above-described prior art cannot solve the technical problem described below. That is, when the friction force is applied between the magnetic disk and the magnetic head slider, the pitch angle of the magnetic head slider is reduced, whereby, owing to an edge wear on the leading edge side of the magnetic head slider due to the increase of the friction force, owing to a generation of the self-excited vibration of the suspension and owing to the generation of the forced vibration of the suspension due to the varying friction force, the space between the magnetic head and the magnetic disk cannot be constantly kept, and thus stable magnetic recording is difficult.